Yoshinobu Ezura

Yb 3+ -doped CaF 2 -LaF 3 ceramics laser

Highly transparent ceramic is an attractive gain medium for high-power lasers due to its high fracture toughness, homogeneity, and size scalability. Here we report the first Yb³⁺-doped CaF₂-LaF₃ ceramics laser. Codoping of La³⁺ ion can reduce the formation of Yb²⁺ ions and enhance the laser efficiency. In the laser experiment, the maximum output power of 4.36 W and the maximum slope efficiency of 69.5% were obtained with a 3% La, 2% Yb sample and a 2% La, 1% Yb sample, respectively. Due to the combined properties of Yb:CaF₂ and a ceramic laser gain medium, Yb:CaF₂-LaF₃ ceramic is a promising gain medium for a high-power ultrashort pulse laser and amplifier.

Highly efficient Yb 3+ -doped CaF 2 -LaF 3 ceramic laser

We prepared transparent Yb:CaF<inf>2</inf>-LaF<inf>3</inf> ceramics with different combinations of doping concentrations of Yb³⁺ and La³⁺ and obtained CW laser operation with maximum output of 3.97 W. The maximum slope efficiency was as high as 73.1%.